The present disclosure relates to semiconductor device fabrication. More particularly, the present disclosure relates to using a trilayer stack including a photoresist layer, a wet-strippable titanium-containing antireflective coating (TiARC) layer and an organic planarization layer (OPL) as a block mask to minimize substrate damage during lithographic patterning.
A Fin field effect transistor (FinFET) is a promising device structure for scaled complementary metal-oxide-semiconductor (CMOS) logic and memory applications in 22 nm technology and beyond due to its good short channel effect (SCE) controllability and its small variability. The manufacture of FinFETs with high aspect ratio topography in CMOS devices can be challenging because conventional block masks used to form various patterning features are very difficult to completely remove and a reactive ion etch (RIE) that is performed to remove any residue of the block masks often results in surface damage to the substrate. Such damage can have a negative impact on the characteristics of FinFETs. Therefore, there remains a need to develop a block mask scheme that can be easily removed by wet chemical etching to avoid damages to the substrate as well as the components of the FinFETs.